Selective control valve mechanism



March 8, 1966 A. J. WILSION 3,239,034

SELECTIVE CONTROL VALVE MECHANISM Original Filed Sept. 5, 1962 4Sheets-Sheet 1 ALEXANDER J W/LSO/V March 8, 1966 A. J. WILSON 3,239,034

SELECTIVE CONTROL VALVE MECHANISM Original Filed Sept. 5, 1962 4Sheets-Sheet 2 ALEK/M/DER J W/Lso/v B -M & ar/[Am March 8, 1966 A. J.WILSON 3,239,034

SELECTIVE CONTROL VALVE MECHANISM Original Filed Sept. 5, 1962 4Sheets-Sheet 5 Fig.5

Z 4 O G a33eI3/ A ALEX/"V052 [4/1/430 March 8, 1966 A. J. WILSON3,239,034

SELECTIVE CONTROL VALVE MECHANISM Original Filed Sept. 5, 1962 4Sheets-Sheet 4 Aux fin/DE J. 14/1160 5 .-mw A? PM United States Patent 3239,034 SELECTIVE CONTROL VALVE MECHANISM Alexander John Wilson, SuttonColdfield, Warwickshlre, England, assignor to Girling Limited,Birmingham, England, a British company Continuation of application Ser.No. 221,485, Sept. 5, 1962. This application July 1, 1965, Ser. No.472,391 6 Claims. (Cl. 188-452) This application is a continuation of myprior application, Serial No. 221,485, filed September 5, 1962, nowabandoned.

This invention relates to improvements in selective control valvemechanism which is intended primarily for controlling the application offluid pressure brakes on the wheels on opposite sides of a vehicle, suchas a tractor, but can be used for other purposes where there are similarrequirements.

My invention comprises a control valve system for selectivelycontrolling the delivery to separate slave cylinders or the like ofliquid from a master cylinder or other source of liquid under pressurein which normally open valves are interposed between the source ofpressure. liquid and-separate slave cylinders or groups of slavecylinders and the valves normally allow pressure liquid to pass to bothslave cylinders or groups of slave cylinders; but are selectivelyactuated by control means to restrict or prevent the delivery ofpressure liquid to one or other of the slave cylinders or groups ofslave cylinders.

" In the application of our invention to a braking system for a tractoror like vehicle in which a master cylinder supplying liquid underpressure to the slave cylinders of brakes on wheels on opposite sides ofthe vehicle is actuated by operation of either or both'of two pedals themaster cylinder is connected to the slave cylinders through a controlvalve system incorporating two normally open valves which are notaffected by simultaneous depression of both'pedals butof which one isclosed or allowed to close on depression of one pedal.

Some embodiments of my invention are illustrated by way of example-inthe accompanying drawings in which: FIGURE 1'- is a side elevation of adual pedal control for hydraulic brakes on a tractor or like vehicle;

FIGURE 2 is a plan of the control-shown in FIG- URE 1;

FIGURES 3 and 4 are vertical sections on line 3-3 of FIGURE 1 showingthe valve controlling means in two different positions; 1

FIGURE 5 is a vertical section of a selector valve suitable for use inthe control shown in FIGURES 1 and 2;

FIGURE 6 is a section on the line 6-6 of the valve shown in FIGURE 5,embodying a different type of selector valve; I I

FIGURE 7 is a fragmentary section of another type of valve;

FIGURE 8 is a section of a further form of valve; and

FIGURE 9 is a section on the line 9--9 of FIGURE 8.

In the dual pedal control for an hydraulic braking system shown inFIGURES l to 4, the brakes on wheels on opposite sides of a vehicle areadapted to be applied by depression of either'or both of two pedals 10,11.

Application of the brakes on one side of the vehicle for steering iseffected by depression of the appropriate pedal and application of thebrakes on both sides for retarding the progress of the vehicle iseffected by depressing both pedals which can be coupled together by apivoted latch 12 in the known manner for simultaneous operation.

The pedals are freely mountedon a transverse shaft 13 which is itselfmounted for angular movement in a fixed of the vehicle.

bracket 14. A boss 15 fixed on the shaft between the pedals has adepending arm 16 for actuating the piston of an hydraulic mastercylinder 17 from which liquid under pressure is forced to the slave orwheel cylinders of the brakes on opposite sides of the vehicle through aselector valve 18 mounted on the bracket 14. The boss 15 is coupled tothe pedals by dogs 19 providing a substantial degree of angular lostmotion to allow the boss 15 to be moved angularly by either pedalwithout affecting the other pedal.

The pedals carry fingers 21, 22 projecting rearwardly and adapted toengage opposite ends of a beam 23 carried by a member 24 which isslidably connected to a member 124 pivoted at its lower end to a bossfixed in the bracket 14. The outer lower side of the member 124 carriesan abutment 126 Whose upper side is engaged by the lower end of acompression spring 127 which operates on the member 24 to urge itupwardly until the ends of the beam 23 engage the respective fingers 21,22. The member 124 is coupled to a rocking spindle 25 of the selectorvalve 18 by means of a bifurcated end part 128.

When both pedals are depressed simultaneously, the rocking spindle 25remains in a vertical plane as shown in FIGURE 3 and allows liquid fromthe master cylinder to flow to the slave cylinders of the brakes on bothsides When only one pedal is depressed the spindle 25 is rocked overinto the position shown in FIG- URE 4 and cuts off the supply of liquidto the slave cylinders of the brakes normally applied by depression ofthe other pedal.

The selector valve may conveniently be of the construction shown inFIGURES 5 and 6.

In this valve, liquid from the master cylinder is delivered intoaniinlet port 31 in the bottom of the valve body 32 leading into atransverse bore 33 of which opposite ends are connected to outlet ports34 and 35 adapted to be respectively connected by pipe lines to theslave cylinders of brakes on opposite sides of the vehicle.

A valve member 36 in the form of a piston is axially slidable in thebore 33 and has on opposite ends compressible washers adapted to engageopposite ends of the cylinder when the piston is moved to either side ofthe normal central position shown in the drawings, the .piston havinglongitudinal grooves or flats on its periphery as shown in FIGURE 6 forthe passage of liquid. The position of the piston is controlled by arocking spindle 37 of which the lower end carries or is formed as a ballhead 38 slid-ably engaged in a transverse slot 39 in the piston. At anintermediate point in its length, the spindle is formed with a collar 41having a part-spherical upper surface which is in rocking engagementwith a complementary concave part-spherical surface in -a retaining nut42 screwed on to an upstanding boss 43 on the body through which thespindle passes. The partspherical surfaces on the collar and nut areheld in engagement by a conical spring 44 interposed between the nut andthe upper end of a boot or shroud 45 which fits over the upper part ofthe valve. Below the collar 41 the spindle passes through a conedopening in a hard rubber or otherwasher-46 and through a soft rubbersleeve 47 which acts as a seal and also, in conjunction With the spring44, normally holds the spindle and valve member in the central positionshown. In this position liquid from the master cylinder can flow freelyto both outlet ports. Rocking movement of the spindle in a plane atright angles to the axis of the boss 33 does not affect the position ofthe valve member, but rocking movement in either direction in a planecontaining the axis of the bore moves the valve member axially in thebore and the valve member cuts off communication between the 3 inletport and one or other of the outlet ports according to the direction inwhich the spindle is rocked.

In the valve shown in FIGURE 7, liquid from a master cylinder or thelike is delivered into a chamber 51 in a valve body 52. Passages 53 leadfrom the chamber 51 into the lower ends of spaced vertical bores 54 andpassages 55 lead out of the bores at intermediate points in theirlengths to outlet ports adapted to be connected to slave cylinders whichare to be selectively actuated. Spring-loaded pistons 56 working in theupper parts of the bores 54 and carrying seals 57 are adapted to beselectively operated by opposite ends of a lever 58 on a rocking shaft59. Angular movement of the shaft in either direction causes one end ofthe lever 58 to move the corresponding piston 56 downwardly in its boreto close the passage 55 and cut off communication between the chamber 51and the outlet into which that passage leads.

In the valve shown in FIGURES 8 and 9, liquid from a master cylinder orother source of liquid under pressure is delivered through an inlet port61 into a chamber 62 in a body 63. Spaced outlet ports 64 and 65 areconnected to the chamber 62 through tilting spring-loaded valves 66 and67 of known type having upstanding stem portions 68. These are engagedby resilient fingers on a bar 69 rotatably mounted on a spindle 71 whichis itself rotatably mounted in the valve body. This bar is loaded by atorsion spring 72 which in conjunction with stops 73 maintains the barnormally in such a position that the fingers hold the valves in thetilted or open position so that liquid can flow freely from the inletport 61 to both outlet ports.

The spindle carries at its upper end a cross bar 74 by which it can bemoved angularly, and mounted on the spindle within the chamber 62 is afork 75 which, when the spindle is moved angularly in either directionfrom its normal position, moves the bar 69 and fingers angularly toallow one of the valves to close and so to prevent liquid from passingfrom the chamber into the corresponding outlet port.

In any of the valve assemblies described above, the movement or releaseof a valve member from the open position may be arranged only torestrict or reduce the flow of liquid to a slave cylinder or cylindersinstead of cutting it off completely.

I claim:

1. An hydraulic braking system for a vehicle having two sets of brakesoperable independently and simultaneously, comprising two pedals mountedfor simultaneous and independent angular movement about a fixed axis, amaster cylinder for supplying fluid under pressure to both sets ofbrakes, means operatively connecting the pedals to the master cylinder,a selector valve for controlling the supply of pressure fluid from themaster cylinder to the brakes, means operatively connecting each pedalto the selector valve, said selector valve being normally open to permitpressure fluid to flow from the master cylinder to both sets of brakeswhen both pedals are moved angularly and simultaneously, and meansincorporated in said selector v-alve actuated by differential movementof the pedals to restrict and prevent the supply of pressure fluid toeither set of brakes while permitting the delivery of pressure fluid tothe other set of brakes.

2. An hydraulic braking system for applying independently andsimultaneously sets of hydraulic brakes on opposite sides of a vehicle,comprising two pedals mounted for simultaneous and indepenent angularmovement about a fixed axis, a master cylinder for supplying hydraulicfiuid under pressure to both sets of brakes, means operativelyconnecting the pedals to the master cylinder, a selector valve forcontrolling the supply of fluid pressure from the master cylinder toboth sets of brakes, means operatively connecting each pedal to theselector valve, said selector valve being normally open to permitpressure fluid to flow from the master cylinder to both sets of brakeswhen both peda are moved angularly and simultaneously, and meansincorporated in said selector valve actuated by differential movement ofthe pedals to restrict and prevent the supply of pressure fluid to thebrakes on one side of the vehicle while permitting the delivery ofpressure fluid to the brakes on the opposite side of the vehicle.

3. An hydraulic braking system for supplying fluid to slave cylinders ofbrakes on wheels on opposite sides of a vehicle independently andsimultaneously, comprising two pedals mounted for simultaneous andindependent angular movement about a fixed axis, a master cylinder forsupplying fluid under pressure to both sets of brakes, means operativelyconnecting the pedals to the master cylinder, a selector valve forcontrolling the supply of pressure fluid from the master cylinder to thebrakes, said selector valve comprising a body member, a bore in saidbody member having an inlet connected to the master cylinder and havingat opposite ends outlets for connection to separate slave cylinders onthe wheels on opposite sides of the vehicle, and a valve member workingin the bore and adapted to engage either end of the bore to close theoutlet for that end, a rocking spindle for actuating the valve memberand having a ball end engaging in a slot in the valve member, and meansfor connecting each pedal to the rocking spindle, whereby independentangular movement of either pedal moves the rocking spindle in a planecontaining the axis of the bore in the body member, the valve memberbeing adapted to close the outlet from one end of the bore whilepermitting fluid to flow from the outlet at the opposite end to theslave cylinders of the brakes on one side of the vehicle, and uponsimultaneous angular movement of both pedals pressure fluid is permittedto flow from both outlets to the slave cylinders on the wheels on bothsides of the vehicle.

4. An hydraulic braking system as claimed in claim 3, and including aspring which biasses said rocking spindle into a position in which itnormally holds the valve member in a position midway between the ends ofthe bore.

5. An hydraulic braking system for supplying fluid to slave cylinders ofbrakes on wheels on opposite sides of a vehicle independently andsimultaneously, comprising two pedals mounted for simultaneous andindependent angular movement about a fixed axis, a master cylinder forsupplying fluid under pressure to both sets of brakes, means operativelyconnecting the pedals to the master cylinder, a selector valve forcontrolling the supply of pressure fluid from the master cylinder to thebrakes, said selector valve comprising a valve body adapted to beconnected to the master cylinder, two spaced bores in said valve body,outlet passages leading from the bores and adapted to be connected toseparate slave cylinders on the wheels on opposite sides of the vehicle,pistons working on the bores, a rocking shaft, and a lever on saidrocking shaft of which opposite ends selectively actuate said pistons,and means for connecting each pedal to the rocking shaft, wherebyindependent angular movement of either pedal moves said rocking shaftangularly and moves one of said pistons in its bore to close the outletpassage from that bore while permitting fluid to flow from the outletpassage in the other bore to the slave cylinders of the brakes on oneside of the vehicle, and upon simultaneous angular movement of bothpedals pressure fluid is permitted to flow from both outlet passagesfrom the bores to the slave cylinders on the wheels on both sides of thevehicle.

6. An hydraulic braking system forsupplying fluid to slave cylinders ofbrakes on wheels on opposite sides of a vehicle independently andsimultaneously, comprising two pedals mounted for simultaneous andindependent angular movement about a fixed axis, a master cylinder forsupplying fluid under pressure to both sets of brakes, means operativelyconnecting the pedals to the master cylinder, a selector valve forcontrolling the supply of pressure fluid from the master cylinder to thebrakes, said selector valve comprising a valve body, a chamber in saidvalve body having an inlet connected to the master cylinder and having apair of spaced outlets adapted to be connected to slave cylinders on theWheels on opposite sides of the vehicle, a spring-loaded tilting valvecontrolling each outlet, and spring-loaded means adapted to normallyhold open said tilting valves, an angularly movable control memberconnected to the pedals and operable upon angular movement of eitherpedal to close one of said tilting valves and prevent pressure fluidfrom flowing to the slave cylinders on the wheels of that side of thevehicle, and upon simultaneous angular movement of both pedals, saidspring-loaded means are adapted to hold open both said tilting valvesand fluid is permitted to flow from the chamber in said valve body pastboth tilting valves and to the slave cylinders on the Wheels on bothsides of the vehicle.

References Cited by the Examiner UNITED STATES PATENTS 829,120 8/1906Mumford 137625.5 2,556,287 6/1951 Milster 188-152 2,741,337 4/1956Ziskal 188152 3,180,360 4/1965 Paulin 137625.5

MILTON BUCHLER, Primary Examiner.

G. E. A. HALVOSA, Assistant Examiners.

1. AN HYDRAULIC BRAKING SYSTEM FOR A VEHICLE HAVING TWO SETS OF BRAKESOPERABLE INDEPENDENTLY AND SIMULTANEOUSLY, COMPRISING TWO PEDALS MOUNTEDFOR SIMULTANEOUS AND INDEPENDENT ANGULAR MOVEMENT ABOUT A FIXED AXIS, AMASTER CYLINDER FOR SUPPLYING FLUID UNDER PRESSURE TO BOTH SETS OFBRAKES, MEANS OPERATIVELY CONNECTING THE PEDALS TO THE MASTER CYLINDER,A SELECTOR VALVE FOR CONTROLLING THE SUPPLY OF PRESSURE FLUID FROM THEMASTER CYLINDER TO THE BRAKES, MEANS OPERATIVELY CONNECTING EACH PEDALTO THE SELECTOR VALVE, SAID SELECTOR VALVE BEING NORMALLY OPEN TO PERMITPRESSURE FLUID TO FLOW FROM THE MASTER CYLINDER TO BOTH SETS OF BRAKESWHEN BOTH PEDALS ARE MOVED ANGULARLY AND SIMULTANEOUSLY, AND MEANSINCORPORATED IN SAID SELECTOR VALVE ACTUATED BY DIFFERENTIAL MOVEMENT OFTHE PEDALS TO RESTRICT AND TO PREVENT THE SUPPLY OF PRESSURE FLUID TOEITHER SET OF BRAKES WHILE PERMITTING THE DELIVERY OF PRESSURE FLUID TOTHE OTHER SET OF BRAKES.